An image capture apparatus has been proposed in which the exit pupil of the imaging lens is divided into multiple pupil areas, and multiple parallax images corresponding to the divided pupil areas can be captured at the same time.
U.S. Pat. No. 4,410,804 discloses an image capture apparatus that uses a two-dimensional image sensor in which one microlens and multiple divided photo-electric converters are formed with respect to one pixel. The divided photo-electric converters are configured so as to receive light from different pupil sub-areas of the exit pupil of the imaging lens via one microlens, and thus pupil division is performed. Multiple parallax images that correspond to the divided pupil sub-areas can be generated from the signals obtained due to light reception in the divided photo-electric converters. Japanese Patent Laid-Open No. 2001-083407 discloses the generation of a captured image by adding together all of the signals obtained due to light reception in the divided photo-electric converters.
The multiple parallax images that are captured are equivalent to light field (LF) data, which is information on a spatial distribution of light intensity and an angle distribution. Stanford Tech Report CTSR 2005-02, 1 (2005) discloses refocusing technology in which the focal position of a captured image is modified after capturing by compositing an image at a virtual image forming plane that is different from the image sensing plane using LF data that has been acquired.
However, although multiple parallax images can be acquired at the same time in the above-described conventional examples due to dividing the exit pupil of the imaging lens into multiple areas, there is the problem of a reduction in the spatial resolution of the captured image that is generated from the parallax images.